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Kooltherm K21 Rainscreen Board is a phenolic foam insulation board with a fiber-free core. It has a permeable non-woven glass fibre facer on the back and a black perforated alu multilayer facer on the front . The board is vapor diffusion-inhibiting, meaning it helps to significantly reduces the build-up of water vapor in the construction. It is ideal for applications where controlling moisture movement is critical to prevent condensation and maintain building integrity.
Product Highlights
Reaction to fire (EN 13501-1): B-s3,d0
λD-value 0,022 W/(m·K) (20-39mm)
λD-value 0,021 W/(m·K) (40 -159 mm)
Vapor diffusion-inhibiting
Ideal for ventilated facades with an open structure, due to the black facer
Helps you reach the required U-values with a thinner build-up compared to mineral wool alternatives